Radiotelephone

ABSTRACT

An electronic radiotelephone comprising: a first housing; a second housing releasably attachable to the first housing to meet with the first housing around the periphery of the radiotelephone; and retaining means comprising a cover for holding the electronic components of the radiotelephone to the first housing when the second housing is released from attachment with the first housing.

[0001] This invention relates to a radiotelephone.

[0002] It has become desirable to be easily able to replace housingparts of radiotelephones. For example, customers may want to replace abroken or scratched housing for repair purposes, or to change theappearance of a radiotelephone by replacing its housing with another ofa different appearance. Also, there may be a need for radiotelephones tobe supplied to dealers without being fully housed, so that the dealerscan fit distinctive housings of their own before the radiotelephones aresold. Normally it is the user interface housing of the phone that isreplaced in this way.

[0003] Normally, when housing parts of a phone, especially userinterface housing parts, are removed the internal components of thephone become loose and/or exposed and there is a significant risk ofthem being damaged. This makes it risky for unskilled people to replacethe phone's housing parts, or for phones to be shipped in a partiallyhoused state.

[0004] According to the present invention from one aspect there isprovided: an electronic radiotelephone comprising: a first housing; asecond housing releasably attachable to the first housing to meet withthe first housing around the periphery of the radiotelephone; andretaining means comprising a cover, for holding the electroniccomponents of the radiotelephone to the first housing when the secondhousing is released from attachment with the first housing.

[0005] The cover may extend over all or some of the electroniccomponents of the phone. If the cover does not extend over all thecomponents then the retaining means may comprise further articles suchas a circuit board or another cover. The cover preferably retains userinterface components such as a microphone, a speaker, a display or akeymat. The cover preferably has means to allow communication betweenthe retained user interface components and a user—for example atransparent or translucent portion, a deformable portion or a hole oraperture. The cover may hold one or more seals behind it, preferably forsealing around user interface components and, most preferably,associated apertures.

[0006] The cover is preferably attachable to the first housing, eitherdirectly or via other components of the retaining means. The cover ismost preferably releasably attachable—for example by spring clips.

[0007] The first and second housings preferably provide front and rearouter casings for the radiotelephone. The housings preferably meetaround substantially all of the perimeter of the radiotelephone,although there may suitably be regions where they do not meet—forexample to provide access to the interior of the phone (e.g. forconnectors).

[0008] At least one user interface component may be held captive betweenthe second housing and the retaining means when the second housing isattached to the first housing. That said component is preferably acomponent which is visible, most preferably over a substantial region ofthe surface of the radiotelephone, when the radiotelephone is assembled.The component is preferably a keymat.

[0009] The cover preferably holds a keymat and/or a member that providesat least one user-actuable key to the first housing.

[0010] According to the present invention from a second aspect there isprovided an electronic device having a housing which has a housing wallwith openings for control elements and/or display elements,characterised by attachment means for detachably connecting to thehousing an external wall element which at least partially covers thehousing wall, the external wall element having openings which arealigned with the openings in the housing wall.

[0011] When the housing wall provided with openings is covered by theexternal wall element, the openings provided in the housing wall and inthe external wall element are preferably aligned with one another sothat for example the push-button keys which may project through theopenings can continue to be used even after the external wall element isfitted on to the housing wall and/or so that display elements which maybe inserted into the openings can be read. This preferably also appliesto microphones or loudspeakers which may be inserted into theopenings—for example in the case of cordless telephones.

[0012] By means of either aspect of the invention, the electronicsprovided in the device may suitably be protected against access by thecustomer when the external appearance of the housing is modified. Then,if one external wall element is to be replaced by another in order togive the electronic device a new design there is a reduced risk of theelectronics present in the housing being damaged when the external wallelements are interchanged, or of the user being subjected to danger bythe electronics present inside the housing. The external wall elementscould even be interchanged when an electronic device is operating.

[0013] According to an advantageous refinement of the invention, theexternal wall element can engage, at least partially, over furtherhousing walls of the housing so that the design of the housing can bemodified to an even greater extent or adapted to the wishes of the userto an even greater degree.

[0014] The profile of the external wall element can preferably followthe profile of the housing walls of the housing, for instance ifemphasis is being placed not so much on the modification of the shape ofthe housing but on changing the colour or the type of material of thehousing. Alternatively, the external wall elements can have differentshapes (which can also deviate from one another to a greater degree)provided it is ensured that after the respective external wall elementshave been connected to the housing respective openings in the fitted-onexternal wall element and in the housing wall in question are alignedwith one another.

[0015] The external wall element can preferably be of, for example,shell-shaped design so that it can be fitted for example with one edgeon to a base which projects outwards beyond the side walls of thehousing.

[0016] Any desired attachment means can be used to attach the externalwall element to the housing of the electronic device, but attachmentmeans with press-on/catch closure can preferably be used. Theypreferably ensure a secure connection between the external wall elementand the housing and, moreover, can suitably be easily used without aspecial tool being required for them.

[0017] The present invention will now be described, by way of example,with reference to the accompanying drawings, in which:

[0018]FIG. 1 shows a radiotelephone of a first embodiment with itsexternal wall element removed;

[0019]FIG. 2 shows the radiotelephone of FIG. 1 with the external wallelement fitted;

[0020]FIG. 3 shows a view of the interior of housing 14 of theradiotelephone of FIG. 1;

[0021]FIG. 4 shows a cross-section through part of the housing of FIG.3; and

[0022]FIG. 5 shows an exploded view of a second embodiment of, theinvention.

[0023] The invention is explained below with reference to twoembodiments of mobile phone.

[0024]FIG. 1 shows a mobile phone having a housing 1 with which aplate-shaped base element 2 and a shell-shaped housing element 3 areassociated. The plate-shaped based element 2 and the shell-shapedhousing element 3 are connected to one another using screws (notillustrated) which project upward through openings 4 in the shell-shapedhousing element 3 and are screwed into sockets (not illustrated) whichare fixedly connected to the inside of the plate-shaped base element 2.Inside the housing 1 there is a carrier plate or circuit board forelectronic components etc., attached in a suitable way.

[0025] The shell-shaped housing element 3 has a housing wall 5 which isdisposed essentially parallel with the plate-shaped base element 2 andlocated at a distance therefrom and is integral with side walls 6 whichare supported with their free or lower edge on the plate-shaped baseelement 2. In this arrangement, the plate-shaped base element 2 projectsoutwards beyond the side walls 6 by constant distance in its edge regionso that a profile with an identical contour is obtained.

[0026] In the housing wall 5 there is a plurality of through-openings 7through which components inside the housing 1 partially project. Thethrough-openings 7 can be provided for, for example, push-button keys 8,a display device 9 or a loudspeaker device/microphone device 10. Acorresponding through-opening may also be present in the rear side wall6′ for an aerial.

[0027] On each of the side walls 6 extending in the longitudinaldirection of the housing 1 there are two attachment means 11, at adistance from one another, which are designed as push fit/catchclosures. They are located in each case near the front and rear ends ofthe telephone. The attachment means 11 have a catch projection 12 whichis biased outwards in a sprung fashion and can be pressed inwards intothe housing 1 against the outwardly acting spring force by means of anexternally accessible activation element 13. The attachment means serveto attach to the housing 1 an external wall element 14 which is fittedover the shell-shaped housing element 3 and is also of shell-shapeddesign.

[0028] The shell-shaped external wall element 14 which is illustrated inFIG. 1 has approximately the same contour as the shell-shaped cover 3but is designed in such a way that it can receive the shell-shapedhousing element 3 in it. If the external wall element 14, which isdesigned as a thin-walled shell, is fitted on to the shell-shapedhousing element 3, the shell-shaped external wall element 14 issupported with the free or downwardly pointing edge of its side walls onthat part of the plate-shaped base element 2 which projects outwardsbeyond the shell-shaped housing element 3. Here, the wall thickness ofthe side walls of the shell-shaped external wall element 14 correspondsto the distance by which the edge of the plate-shaped base element 2projects outwards beyond the side walls 6, 6′ of the shell-shapedhousing element 3. As a result, no step remains in the connection areabetween the shell-shaped external wall element 14 and the plate-shapedbase element 2. The height of the side walls of the shell-shapedexternal wall element 14 can be selected such that the main face of theexternal wall element 14 comes to rest at a short distance from thehousing wall 5 and as a result does not exert any pressure on thelatter.

[0029] Openings 7′, which are aligned with the openings 7 in the housingwall 5 of the shell-shaped housing element 3, are provided in the mainface of the external wall element 14. Therefore, it is possible tocontinue to operate the telephone even when the external wall element 14is fitted on to the shell-shaped housing element 3. At the same time,the push-button keys 8 can be of such a height that they also projectoutwards beyond the external wall element 14. Openings which are presentin the external wall element 14 for the display device 9 and theloudspeaker device/microphone device 10 can be covered, for example bymeans of a transparent element 15 or a grille 16.

[0030]FIG. 2 shows the cordless telephone or mobile phone in a state inwhich the shell-shaped external wall element 14 is fitted on to theshell-shaped housing element 3 and is detachably connected to thehousing 1. On the internal faces of the long side walls of the externalwall element 14 there are notches for the catch projections 12 of theattachment means 11 so that the catch projections 12 engage in thenotches as a result of the outwardly pressing spring force, and thushold the external wall element on the housing 1. In this state, theactivation elements 13 are also pushed outwards but only to such anextent that they do not project beyond the side edge of the plate-shapedbase element 2 or of the external wall element 14. The activationelements 13 can extend here in a groove 17 in the upper face of theplate-shaped base element 2. If the activation elements 13 are pressedinwards, that is to say inwards along the groove 17, for example using apointed object, they move the catch projections 12 correspondinglyinwards along with them so that the said catch projections 12 disengagefrom the notches on the inside of the side walls 6 of the external wallelement 14. The external wall element 14 can then be removed from thehousing 1.

[0031] The external wall element 14 is fitted on to the housing 1 bysimply pressing it on. The catch projections 12 then engageautomatically in the notches.

[0032]FIG. 5 shows an exploded view of another embodiment. The mobilephone of FIG. 5 has two outer housings 18, 19. The housings matetogether around the periphery of the phone to enclose almost all of thephone's components.

[0033] The lower housing 18 has a rear recess 18 a, to accommodate afirst circuit board 20, and a front shelf 18 b to provide support behindthe phone's keypad. The circuit board 20 carries and connects togetherelectronic components, including RF (radio frequency) componentsshielded within RF shields 21. A two-part connector 22 is provided toallow for push-fit electrical connection between circuit board 20 and asecond circuit board 23. Circuit board 23 carries other electroniccomponents, including a buzzer 24 (for generating a telephone ringingtone) and an electrical connector 25 (for allowing external connectionsto be made to the phone—for example to program the phone or connect anexternal antenna).

[0034] A microphone 26 fits in a recess 25 a in the connector block. Themicrophone is surrounded by a rubber sleeve or an o-ring 27 to hold itsecurely, by friction, in the recess 25 a. The microphone has concentricelectrical connection pads on its lower surface to connect to springfingers on the circuit board 23 underneath it irrespective of themicrophone's orientation relative to the circuit board.

[0035] Circuit board 23 has a region 28 of exposed printed conductivezones for co-operating with conductive portions of keypad membrane 29 toprovide a touch-sensitive keypad. When the membrane is fixed by adhesiveto the circuit board flexible domed regions 29 a of the membrane can bepressed to the circuit board to act as key switches for sensing pressurefrom a user. When the phone is fully assembled each domed region fallsbelow one of the keys 24 a of keymat 24 so that a user can actuate thekey switches.

[0036] A translucent plastics frame 32 fits to the rear end of circuitboard 23. The frame carries an LCD (liquid crystal display) unit 30 anda reflector 31. The frame defines a recess 32 a dimensioned to receive aspeaker 33. The speaker has sprung rear connectors which, when the phoneis assembled and the speaker is pressed towards the circuit boardconnect to corresponding connection pads on the circuit board 23.

[0037] To assemble the phone, circuit board 23 is screwed by means ofscrews 40 to the rear housing 18, holding the circuit board 20 in placebehind it in the recess 18 a. Microphone 26 is inserted in recess 25 aand held in place by the friction of its o-ring 27 against the walls ofthe recess; at the same time the connections to the microphone are madeby the spring fingers. Membrane 29 is fixed by adhesive to the circuitboard 23. The frame 32 is offered up to the rear end of circuit board 23and display unit 30 is soldered to the circuit board 23 to make theconnections to the display. Speaker 33 is then set in the correspondingrecess 32 a, with its spring contacts against the speaker contact padson circuit board 23.

[0038] Next gasket 34 is placed over the frame/display assembly to sealaround the edges of the speaker 33 and display device 30. The gasket isformed of flexible rubber with sealing walls that surround holes 34 a,34 b for the speaker and display device. The gasket also includes aprojecting key portion 34 c whose upper end, when the phone has beenfully assembled, projects through hole 19 a in the upper housing 19. Thekey portion is flexible and has a conductive coating of carbon ink onits lower end which can make contact with corresponding tracks on thecircuit board 23 when the upper end of the key portion is pressed by auser.

[0039] A retaining frame 35 is then pushed into place over the gasket tohold the gasket, the speaker 33, the LCD unit 30 and the frame 32 to thecircuit board 23. The frame 35 has a generally flat top surface 36 andside walls 37. The frame is stamped from aluminium sheet around 80 μmthick. The top surface 36 of the frame has a hole 35 a for the display,a hole 35 b for the key portion 34 a, a hole 35 c for a locating pin 32b on the plastics frame 32 and a grille 35 d of holes for the speaker33. When the frame 35 is pushed into place it squeezes the speaker andthe LCD unit between the circuit board 23 and the gasket 34. The sidewalls of the cover are forced out slightly and then spring back as clips38, bent from the side walls 37, engage the lower surface of the circuitboard 23. The frame 35 thus clips into place and by bending the wallsoutward again the cover can be removed if needed. The clips 38 then holdthe frame to the circuit board 23 and by means of the frame the gasket,the display unit and the speaker are held to the circuit board 23. Forsecurity a screw 39 is then inserted through holes in the upperprojection, the plastics frame 32, and the circuit board 23 and theninto the lower housing 18.

[0040] The antenna 40 is screwed in place in the lower housing 18.

[0041] At this stage in the assembly process only two components of thephone are loose from the assembly mounted to the rear housing 18; thekeymat 24 and the front 19 with its display window 41 fixed in place byadhesive. To complete the assembly process the keymat is sat on themembrane 29, the front housing is mated to the rear housing and the twoare screwed together with screws 43.

[0042] The present invention may include any novel feature orcombination of features disclosed herein either explicitly or implicitlyor any generalisation thereof irrespective of whether or not it relatesto the presently claimed invention or mitigates any or all of theproblems addressed. In view of the foregoing description it will beevident to a person skilled in the art that various modifications may bemade within the scope of the invention. For example, it will beappreciated that the invention may be applied to a wide range ofelectronic devices such as calculators and personal organizers as wellas radiotelephones.

1. An electronic radiotelephone comprising: a first housing; a secondhousing releasably attachable to the first housing to meet with thefirst housing around the periphery of the radiotelephone; and retainingmeans comprising a cover, for holding the electronic components of theradiotelephone to the first housing when the second housing is releasedfrom attachment with the first housing.
 2. An electronic radiotelephoneas claimed in claim 1, wherein the second housing is a user interfacehousing of the radiotelephone.
 3. An electronic radiotelephone asclaimed in claim 1 or 2, wherein the retaining means comprises a circuitboard of the radiotelephone.
 4. An electronic radiotelephone as claimedin claim 3, wherein at least one key sensor is provided on an outersurface of the circuit board.
 5. An electronic radiotelephone as claimedin claim 3 or 4, wherein the cover is arranged to hold components of theradiotelephone between it and the said circuit board.
 6. An electronicradiotelephone as claimed in any of claims 3 to 5, wherein the cover isreleasably engageable with the circuit board
 7. An electronicradiotelephone as claimed in any preceding claim, wherein at least oneuser interface component is retained by the cover.
 8. An electronicradiotelephone as claimed in claim 7, wherein the cover includes anaperture overlying at least one user interface component retained by thecover.
 9. An electronic radiotelephone as claimed in any precedingclaim, wherein a sealing member is retained by the cover.
 10. Anelectronic radiotelephone as claimed in any preceding claim, comprisingat least one key unit for user-actuation of a key sensor, and whereinwhen the second housing is released from attachment with the firsthousing the key unit is free to move with respect to the first housing.11. An electronic radiotelephone as claimed in any preceding claim,comprising at least one key unit for user-actuation of a key sensor, andwherein when the second housing is attached to the first housing the keyunit is sandwiched between the second housing and the key sensor.
 12. Anelectronic radiotelephone as claimed in claim 10 or 11, wherein the keyunit is a key mat.
 13. An electronic radiotelephone as claimed in claim11 or 12, wherein the key sensor comprises a membrane switch.
 14. Anelectronic radiotelephone substantially as herein described withreference to the accompanying drawings.